Method of controlling motor-driven devices adapted to be directed onto moving targets and apparatus for applying the method

ABSTRACT

Method and apparatus for controlling motor-driven devices adapted to be directed onto a moving target, such as weapons, particularly guns, or target acquisition devices, particularly optical sighting device, radar apparatus, sound locators or infrared tracking apparatus, the target being followed by at least one of these devices and the control quantities for the drive of the devices adapted to be directed onto a moving target being calculated by computer means, wherein based on the values of the lateral angle and elevation angle which values are derived continuously from one of the devices adapted to be directed onto a moving target, and on the values of the target velocity and the angle of inclination of the target path with respect to the horizontal plane, on the basis of the geometrical relationships which hold true for a rectilinear uniform movement, the lateral angular velocity and the elevational angular velocity are calculated and fed to the drives of the devices adapted to be directed onto a moving target.

Pitt 3 w 7'9 8 s .12 0

. gs e: '1 t i Kaaz METHOD OF CONTROLLING MOTOR-DRIVEN DEVICES ADAPTEDTO BE DIRECTED ONTO MOVING TARGETS AND APPARATUS FOR APPLYING THE METHOD[75] Inventor: Albert Kaaz,

Duisburg-Grossenbaum, Germany Assignee: Rheinmetall GmbH, Dusseldorf,

Germany Filed: June 2, 1970 Appl. No.: 42,769

[30] Foreign Application Priority Data June 4. 1969 Germany 1928483 US.Cl. 235/615 S, 235/615 E. 318/591 Int. Cl. G061 15/58, 606g 7/80 Fieldof Search... 235/615 R. 61.5 E, 61.5 DF, 235/615 S; 89/41 R, 41 A, 41 B,41 D, 41

M; l78/DlG. 21; 318/591 [56] References Cited UNlTED STATES PATENTS Kuhn178/D1G. 21 McAdam 89/41 R Pun 235/615 R Salomonsson 235/615 E [451 Mar.19, 1974 3.288.030 11/1966 Lind 89/41 R 3.277.282 10/1966 Kuhlenkamp235/6l.5 R 3.064.884 11/1962 Crowther et a1. 235/615 E PrimaryExaminer-Felix D. Gruber Attorney, Agent, or Firm-Craig & Antonelli [5 7ABSTRACT Method and apparatus for controlling motor-driven devicesadapted to be directed onto a moving target. such as weapons.particularly guns, or target acquisition devices, particularly opticalsighting device, radar apparatus, sound locatorsorn'nfrai'ed't'rakififapparams, the target being followed by at leastone of these devices and the control quantities for the drive of thedevices adapted to be directed onto a moving target being calculated bycomputer means, wherein based on the values of the lateral angle andelevation angle which values are derived continuously from one of thedevices adapted to be directed onto a moving target.

and on the values of the target velocity and the angle of inclination ofthe target path with respect to the horizontal plane, on the basis ofthe geometrical relationships which hold true for a rectilinear uniformmovement, the lateral angular velocity and the elevational angularvelocity are calculated and fed to the drives of the devices adapted tobe directed onto a moving target.

17 Claims, 11 Drawing Figures FIG.1

INVENTOR ALBE RT kAA'L cm' qnllmawi, sum 1- Hill AT TO RN EYSPATENTEDHAR 19 m4 INVENTOR ALB RT KAPFL Calla, [Infant-f, )lmvul 'I II.

ATTORNEYS PATENTEU MAR I 9 i974 SHEET '4 OF 8 m QE INVENTOR ALBERT RM-nui student flu ATTORNEYS PAIENTEDHAR 1 9 m4 3798L420 SHEEI 8 I]? 8 INVEN TOR ALBERT KAAL BY A C 0 Qn'bnelli, SreumnP-v ATTORNEYS METHOD OFCONTROLLING MOTOR-DRIVEN DEVICES ADAPTED TO BE DIRECTED ONTO MOVINGTARGETS AND APPARATUS FOR APPLYING THE METHOD This invention relates toa method of controlling motor-driven devices adapted to be directed ontomoving targets and an appratus for applying the method.

This invention further relates to a method and an apparatus for changingfrom manual to automatic control of the aforementioned motor-drivendevices.

Motor-driven devices such as weapons or target acquisition devices inthe form of optical sighting devices, radar apparatus, sound locators orinfrared tracking apparatus are mounted for pivotal movement about twoaxes, a vertical axis and axis at 90 to the vertical axis. In order toalign such devices on moving targets, especially high-speed aerialtargets, hydraulic or electrical drives are utilized which areconstructed such that the operator need only perform simple operationsto control the drive. For example, drives are known in which a singlecontrol lever serves for controlling both directional movements of thetarget acquisition device or weapon.

It has been found that in the case of fast moving targets the operationof such drives is nevertheless very difficult because due to the rapidchanges in the angular velocities with which the gun or the targetacquisition device must be moved about the two axes, the control leverpositions also change rapidly and the operator is not always able tofind the correct positions of the controls. To obviate thesedifficulties, an anticipatory control is already known in whichoperation is facilitated by restricting movement of the control lever.For this purpose. the control lever is lead in a radial guide of arotating disc and the direction of movement of the control lever ispredetermined by automatic rotation of the disc with the guide inaccordance with the result of a computing process so that the operatoronly has the task of adjusting the magnitude of the deflection of thecontrol lever manually in the direction predetermined by the guide.

In known apparatus an estimation of the target velocity and the distanceto the change-over-point is generally necessary, the change-over-pointdistance being the shortest distance between the devices to be alignedon the target and the target path.

Since the weapon operator looks only at the target and the trackingoperation is very short in the case of high-speed targets, theestimation of the distance to the change-over-point must be regarded asdifficult and never accurate.

it is an important object of this invention to provide a method ofcontrolling motor-driven devices adapted to be directed onto movingtargets and an apparatus for applying this method in order to obviatethe aforementioned disadvantages. Proceeding from a method forcontrolling different types of motor-driven devices mounted for movementabout two axes and adapted to be directed onto moving targets, thetarget being followed by at least one of these devices and the controlquantities for the drive of the devices adapted to be directed ontomoving targets being calculated by computer means, this problem issolved according to the invention in that based on the values derivedcontinuously from one of the devices adapted to be directed onto movingtargets of the azimuth or lateral angle a and of the elevation angle Q5and on the values, assumed constant for a given target trackingoperation of the target velocity v and of the angle of inclination e ofthe target path with respect to the horizontal plane, on the basis ofthe geometrical relationships which hold true for a rectilinear uniformmotion the azimuth angular velocity 0),, and the elevational angularvellcity an, are calculated and fed to the drives of the devices adaptedu sfl dfit iq QYiFL The invention affords the advanta g ezfsubstantiallysimplifying and automating the tracking. The calculation of the controlquantities for the drive of the target acquisition device and/or gun orrocket is advantageously based in known manner on a representation ofthe target movement in polar coordinates in a cotangent plane assumed atconstant height. To take account of the angle of inclination to of thetarget path to the horizontal plane, according to the invention theangle ill between the projection of the target path in the cotangentplane and the projection of the associated horizontal in the cotangentplane may be calculated. The angle of inclination to and the targetvelocity v are preferably estimated. It is of course also possible tomeasure these quantities and to base the calculation on the measuredvalues.

If a target acquisition device is used which is mounted on a weapon andparticipates in the movement thereof, according to the invention thelateral and elevation lead angles A and u and the gravity compensationangle a may be calculated and the target acquisition device set back bythese angles with respect to the gun.

1 A substantially automatic tracking nay beachieved according to theinvention in that the quotient wfivrnin formed from the horizontalcomponent of the target velocity v and the minimum value wmin of thehgrigontal component of the t aYg et range and being constant forasixsultaqkinst determined from hsfigtm la z =w/w min sinB by adjustingthe calculated value of the lateral angular velocity w with the value ofthe latra n u r loc ty pl ed xatuau allsxstwnm constructed in a mannerknown per se, preferably during picking up and rapid homing on thetarget, the angle [-3, i.e., the lateral angle measured with respect tothe direction of the track of the target path of the target acquisitiondevice or weapon to be controlled being calculated. The value of thequotient w/w min may then be used as a basis for the calculation of thelateral angular velocity during further tracking, for which the manuallever control may be partially or completely dispensed with.

It is another important object of the present invention to provide amethod and an apparatus which substantially enable a smooth continuoustransition from manual to automatic control of said motor-drivendevices.

In accordance with this invention, this problem is solved in that aftera short initial phase in which the operator directs a target acquisitiondevice manually as accurately as possible onto the target tl i e valties w,

and w of mg lateral ahfele vatlonal velocities suppliedin form ofangular velocities by the manual control are replaced at least partiallyby valves 0 and an? of the lateral and elevational angular vel itiescalculated by the computer means. i i

Preferably a substantially completely, smooth continuous transition frommanual to automatic control is achieved in that the values to, and (Dd,of the lateral and elevational angular velocities supplied by the manualcontrol and the values of these angular velocities supplied by thecomputer means are adjusted to the same level before switching over frommanual to automatic control.

It has been found particularly advantageous when switching from manualto automatic control not to replace the values m. and (0. of the lateraland elevational angular velocities coming from the manual con trolcompletely by the values (11 and (of of the lateral and elevationalangtflar velocities supplied by the computer means but to leave afraction of preferably about 3-20 percent of the values w, and ai and toallow said fraction to be influenced by the manual con- 7 trol forcorrection purposes.

Preferably the fraction of the elevational and lateral angularvelocities which remains under the: influence of the manual controlafter switching to automatic control is infinitely variable.

Some of the objects and advantages of this invention having been stated,others will appear as the descrip tion proceeds when taken in connectionwith the accompanying drawings, in which:

FIG. 1 is a geometrical illustration for deriving the fundamentalequations for the method according to the invention.

FIG. 2 is a separate illustration of a part of the horizontal plane.

FIG. 3 is a separate illustration of a vertical plane through a measuredpoint.

FIG. 3a is an illustration of the angle of elevation.

FIG. 4 is a block circuit diagram of an example of embodiment of thecomputer according to the invention.

FIG. 5 is a block circuit diagram of another embodiment of the computeraccording to the invention.

FIG. 6 is a block circuit diagram of an adapter device which isconnected between the computer and the drive ol the weapon or sight.

FIG. 7 is a basic circuit diagram of a control system contructedaccording to the invention.

FIG. 7a shows a basic circuit diagram of a control system constructedaccording to the invention;

FIG. 8 is part ofthe horizontal plane showing the projection of the pathof movement of the target and FIG. 9 shows an example of embodiment ofan autocontrol apparatus.

FIGS. 1 to 3 illustrate the geometrical relationships, it being assumedthat the target moves with constant velocity v on a straight path P M Twhich is inclined to the horizontal plane at an angle e. The point 0denotes the position ofa gun having a target acquisition device, in thepresent case an optical sighting device. A horizontal plane, the planea, is drawn through the point 0. At the point P the target is picked upby the sighting device for the first time and then tracked. along thestraight line P M T. In the following calculations it is generallyassumed that after target acquisition the operator follows the targetaccurately for a brief moment so that during this initial phase of thetracking accurate manually controlled values of the lateral angle and ofthe angle of elevation are fed to the computer means describedhereinafter. The point M represents the instantaneous position of thetarget and is referred to hereinafter as the instantaneous measuredpoint. The point T is the point of impact, which differs from theinstantaneous measured point M by the lead, which depends substantiallyon the velocity of the target and the time of flight r of the projectileuntil it strikes the target. The point H (FIG. 3) lies vertically abovethe instantaneous measured point M at the same altitude h above theplane E as the point P. The horizontal P H forms with the path of flightP M T the angle of flightpath inclination e, which is generally assumedconstant for a given tracking operation.

A vertical projection of the flightpath onto the plane Eyields in thelatter a line Sp on which lie the points P and T and the point M, whichcoincides with the point H (all points projected onto the plane Earedesignated by a dash). A straight line Sp parallel to the line Sp, isdrawn through the gun position 0 and makes with a null or referencedirection N, which is generally chosen as the North, a course angle wwhich is constant for one tracking operation. For the derivation of theequations by which the computer calculates the control values for theweapon and the sighting device, the so-called cotangent plane, referredto briefly hereinafter as the plane F is introduced in known manner,extending at constant height h above the plane 72'. The line joining thepoint 0 to the moving point of the target passes through the plane E andtraces on said plane a line Sp through the points P, M T which isclearly associated with the true flight path. By projecting the straightline P H into the plane 5 the straight line P H is obtained and formswith the line Sp of the flight path the angle ill which contains theinformation on the flight path inclination c.

On vertical projection of the aforementioned points and straight linesof the plane C onto the plane A congruent points and straight lines areobtained, since these two planes are parallel to each other. Thestraight lines P M. T, and P' H. in the plane A thus also enclose theangle ill (FIG. 2).

The position of the various points is determined in polar coordinates,proceeding from the location 0 of the weapon. in each case by thelateral angle (7 and the elevation angle do. The lateral angle a ismeasured in the horizontal Zi-plane and the elevation angle in thevertical plane, e.g. the d-plane M O M (FIG. 3). The lateral angle (7 ismeasured in the clockwise direction starting from a null or referencedirection N usually coinciding with the North.

The following symbols are also used (cf.FIGS.l-3a):

o-r= w+B Lateral angle ofthepo ir tgf impact or the turntable angle ofthe gun (measureable), w being the course angle constant for onetracking operation between the line Sp or a line Sp parallel thereto andthe reference direction N.

B =0' -Angle between the direction Sp or SPO ancL the straight line GTT.

- B.u= rrAngle between the direction Sp or Sp and the straight line 0M'JWT M d), a 7 Angle of elevation of the gun (measurable).

7 Angle of elevation of the point impact T.

7 Angle of elevation of the instantaneous measured point M.

A Lead angle increment in the lateral direction.

11. Lead angle increment in the elevational direction (not takingaccount of the gravity compensation angle a).

a Gravity compensation angle calculated by means of a ballistic computer(FIG. 3a).

m and u Lateral and elevational velocities with respect to the point ofimpact T. p and q Components of the displacement vector on the line P'T, in the Plane 5 (FIG. 2).

Velocity on the line P T in the plane 6 and on the line P T in the plane5.

Component of v in the direction of the straight line P, H, in the planeFor in the plane 5. Sb

Path of the projectile. Vr

Direction of the sighting device. Wr

Direction of the gun.

The equations derived hereinafter all relate to the gun Pos n at PQlQLLFBPEQE to y" ues B 7 am, ww associated with said weapon position. Therelationship to the measured point which is usually tracked by means ofan optical sighting device, is established by the angular increments Aand p. of the lead. The effect of gravity on the projectile iscompensated for by the gravity compensation angle a.

Firstly, two fundamental equations for the angle and for the trackvelocity v, in the cotangent plane are derived. In FIG. 2 a straightline is drawn from O vertically to the straight line P' M T' andintersects the latter at the point T' and the straight line P' H' at thepoint T", we have coty cot'y sin 8 +il1) wherence sintll/sin (fi llx)tane cot-y The point of intersection of the straight line 0 T' with thestraight line P. H' yields the point T" in the plane a as shown in FIG.2.

The sine law for the triangle P, T, T" leads to v, w, [sinB /siMBri-w],w v (h /h) cos:

It is apparent from this that v, is in no way constant except in thelimiting case:

lim v w constant I in which case it is constant for a single trackingoperation.

The equations for the components p and q of the displacement vector onthe line P T',. in the plane 2? (FIG. 2) are then p h 'cot'y Afi vr n (11 1 A! (Ila) q wa m) vacos (l mb) A! I (lib) Whence HP Q0! (Br -w) (Ill)Equations (I) and (Ill) determine at any instant the an gles 1!: and Bfor given values of h and w. As already stated above, the angle :11 isconstant for a given tracking operation because the flight path of thetarget is assumed to be a straight line. Since o is known the detersincot temp-a5;

To obtain the lead angle increments A and ,u. for the lateral andelevational direction, the result of the following publication is used:

Ein modernes Visier fi'jr leichte Flak by D. Schroder, WehrtechnischeMonatshefte 61, 1964, No. 10, pages 367-373, the equation for A beingtan wfi1" t wherein 1,, is the projectile time of flight, which iscalculated in the ballistic computer.

The following equations are then obtained VI) Equation (VI) being basedon a simplification which assumes that ,u. is small compared withFinally, the range of the weapon from the aerial target is to hedetermined. ltis denoted by w. The following equations are true.

wherein m=hlh and t is the time in which the target covers the distancePM. The factor rrfis also determined from the velocity ratio u-coseAt/Wc'AI.

With the expression for p equation (II) yields p/sinB w At, t constanttime increment. Whence:

In the examples of embodiment of a computer described hereinafter theproduct v hf m c=- p sin Br is formed directly.

The input data w and yr on function 5m are suffcient for the ballisticcomputer. in practice, the type of projectile, temperature, wind andother parameters are also taken into account. The output thereof mustgive the correct gravity compensation angle a and the projectile flighttime t The equations for providing ballistic information are calculatedby means of the ballistic computer B in FIG. 4 and B in FIG. 5, whichballistic computers are constructed to solve the equations in a mannerknown in the art.

FIG. 4 shows a digital computer which is based on the equations derivedabove. By means of the analog digital converter or pulse code converter1 and 2 the lateral angle and the elevation angle Q measured at theweapon are converted into binary form for feeding into the computer. Ablock 3 contains a stabilized oscillator, a counter and a timing devicewhich closes the switches 4 and 5 at constant time intervals Al, forexample every 5 milliseconds, for a short time, i.e., for a time whichis small cmpared with At, to scan new values of 7 and Q5 in each caseand feed these values into the blocks 6 and 7. The block 6 contains tworegisters. A value of 0,- fed into the first register at a given instantwill be transferred to the second register after the time increment A I,when a new value 0', is fed into the first register. AB/Z appears at theoutput of the block 6.

The block 7 contains two registers. The value Q5 is fed into the firstand the value of the gravity compensation angle or obtained from theoutput of a ballistic computer B into the second. y,- appears at theoutput of the block 7 and represents the difference between the values aand w fed into said block, The value y is fed into the block 8, whichcontains a store for associated values of siny und cos'y The outputvalues siny and cosy of the block 8 are fed into the block 9 in whichthe value cot'y is formed which is multiplied in block 10 by theconstant value h thus obtaining h coty This value is now multiplied onthe one hand in the block 11 by the value AB/Z from block 6 to obtainthe value P/2 corresponding to equation (lla). On the other hand thisvalue is fed into the block 12 containing two registers. The value fedinto the first register at a certain instant is transmitted to thesecond register when after passage of the time increment At, a new valueis fed into the first register. Half ofthe difference A(h,-cot'y,-)/2 ofthe values in the two registers appears at the output of the block 12and is equal in accordance with equation (llb) to the half value q/2 ofthe component q of the displacement vector in the plane 2!. The inputvalues for the blocks 11 and 12 are supplied to the latter via switches11', 11" and 12, which are controlled by the timing device in block 3.The output value q/2 from block 12 is divided in block 13 by the outputvalue p/2 of block 11 so that the value q/p appears at the output ofblock 13.

The estimated flight path inclination s will preferably be fed indiscreet values, for example 5, 10, l5, etc. into the block 14 whichcontains binary registers for its output values t sine and cos:Formation of the quotient of these values in block 15 gives the valuetans which is multiplied in block 16 by the value cot-y from block 9 toobtain the value tanecot'y By means of the computing unit consisting ofblocks 17 to 22 and with the aid of the value q/p from block l3 and thevalue tane-cot'y from block 16 the values B and cot (B ll! are obtained.The computing unit includes a block 17 in which the different possiblevalues of cot (8 ll!) and sin (fi 111) are stored and a block 18 whichstores the different values of sin :11. in the blocks 17 and 18 tablesof the desired output values are stored. The output value cot (B I11) ofblock 17, which represents the right-hand side of the equation (lll), iscompared in block 19 with the value q/p from block 13, which representsthe left-hand side of equation (Ill). The output value sin ill fromblock 18 is divided in block 21 by the output value sin (B 111) fromblock 17. The value sin ill/sin(/3 lb) thus obtained, which correspondsto the left-hand side of equation (I), is compared in block 20 with thecorresponding value tanecoty from block 16 representing the right-handside of equation (I).

The store address address 111 appears at the output of the block 20;this address is firstly fed directly into the store block 18 and is thenadded in the block 22 to the store address address ,B coming from block19, thus obtaining-the address (5 ill)", which is fed into block 17. Thestore addresses are systematically modified in the blocks 19 and 20 inaccordance with the result of the comparison in said blocks, whereby newvalues are called up in the store blocks 17 and 18, with which thecomparision operation is repeated until identity in the two blocks 19and 20 is established. When identity obtains the conditions of theequations (1) and (lll) are fulfilled and the correct output valuesaddress [3 and cot(B ill) of the computing unit consisting of the blocks17 to 20 have been found.

The store address address B coming from the block 19 is fed into theblock 23 in which the values of ,B and sinB are stored. The output valuesinB of said block 2 is used as describedl erei nafter to calculate thetarget range w. The output value 8 represents an output value of thecomputer. in addition, the value ,B is simultaneously fed via a switch24 actuated by the timing device in block 3 simultaneously with theswitches 4 and 5 into the block 26 which has a similar function to thatof the blocks 6 and 12 and forms the .va n a measure f bgfla lauslqs ty(um of the lateral rotation of the gun. The value A3 is multiplied inblock 27 by the factor 200. At the output of the block 27 the value(031- is obtained. The value (0 which is equal to AB/At. is obtained bymultiplying AB, derived from the block 26, by the factor 200, since inthe presend embodiment 5 m/sec and 200' A li/sec.

The value (a is calculated in Zfiri with I equation (IV) in anothercomputing unit which includes blocks 26 and 27. For this purpose thevalues sin-y and cos-y are fed from the outputs of the block 8 into theblock 28 in which the value 0,5 sin2y is calculated, which is thenpassed on to the block 29 where it is multiplied by the value cot (8(1!) from block 17. The output value of the block 29 is also multipliedin the bTock 30 by the value (1) from the block 21 so that at the outputof the block 30 the value (0Y1 is obtained in accordance with theequation (IV).

Now that part of the computer is still to be described which with thecooperation of the ballistic computer B calculates the functions tankand tanp. of the lead angle increments A and p. andthegravitygpmpensationalme a. The calculation of the range w between theweapon and target is first describedj it is based on equations (VII) and(IX). In block 31 the estimated flight velocity v, of the target, whichis an input quantity to the computer, is multiplied by the values sineand cos: from block 14, thus obtaining at the two outputs of block 31the values v 'cose and v,,-sine. In block 32 the value v -cose ismultiplied by the constant value h -At the value of h 'A! being madeequal to 1. In block 33 the value p/2 from block 11 is multiplied by thefactor 2 to obtain the value p, which is divided in block 34 by thevalue sinB from block 23. The value v,'h At.coss from block 32 isdivided in block 35 by the value p/sinB obtained at the output of block34. The quantity mh is then obtained at the output of block 35 inaccordance with equation (IX), in being equal to the ratio of theheights h/h From a real time counter reset to zero after each trackingoperation the time t from the instant at which the target was picked upat the point P at an altitude h is fed into block 36 where the time offlight t of the projectile obtained from the ballistic computer is addedthereto. The resetting of the real time counter may be coupled to thesetting of the estimated value of the path inclination angle 6. Thevalue t t is multiplied in block 37 by the quantity v 'sine. The productfrom the output of the block 37 is then deducted in block 38 from thequantity mh from block 35 and the output value of block 38 is thendivided in accordance with equation (VII) in block 39 by the quantitysin'y obtained from block 8-. The value of the target range obtained atthe output of the block 39 is fed into the ballistic computer B.

In addition to the calculated target range the two quantities cosy fromblock 8 and 7 from block 7 are fed into the ballistic computer whichthen calculates therefrom the projectile time of flight t and thegravity compensation angle a, which is an output quantity of thecomputer.

In accordance with equation (V), in block 40 the output quantity tank ofthe computer is calculated as a product of the quantity from theballistic computer B and the angular velocity 605T from block 27. The

output quantity tanp. of the computer is formed in accordance withequation (VI) by multiplying 1 from the ballistic computer B by thequantity ww fron bloclc 30 in block 41.

The value a from the ballistic computer is fed via a switch 42 actuatedsimultaneously with the switches 24, 4 and 5 by the timing device inblock 3 into block 43, which operates in the same manner as block 26 andforms the value Act. Corresponding to the procedure with AB in block 27,in block 44 the value A01 is multiplied by the factor 200 to obtain mwhich is then added in block 45 to the value a from block 30.

output value of the computer.

In the digital computer described above the switches 4, 5, 11, ll", 12',24 and 42 (FIG. 4) are actuated by the timing device 3. The scanningtime of these switches, i.e., the period in which the switches areclosed, is small compared with the time increment At between twoscannings. The computing unit consisting of the blocks 17 to 22generally requires for finding the correct values of B and cot(fi Ill) atime which is greater than the scanning time of the switches but whichshould not be greater than At, so that the total computing time of thedigital computer may be minimized.

The quantity wv =wy +w from bloclg 45 is an FIG. 5 shows an analogcomputer which is equivalent to the digital computer of FIG. 4. Thelateral angle 0 is available as angle of rotation of the gun drive shaftand drives a tachometric dynamo 51 from which the lue of t vsl q t 1 1 pz a nsd no? f of an electrical quantity. The elevational angle 4:, andthe gravity compensation angle a are also fed as shaft angles ofrotation into the computer. In a mechanical substracting device 52,which may be for example a differential gear, a is deducted from thusobtaining 7 which is fed into an electromechanical transducer 53 whichmay include multipliers and function generators for supplying at itsoutputs the following six values in the form of electrical quantities:0.5-sin27 hc-coty cosy, y sin-y and cot y The value cot W is fed into asecond electromechanical transducer 54 at which the estimated flightspeed v, of the target and the estimated path inclination e are alsoset. The transducer 54 may include multipliers and function generatorsfor supplying the three values tane'cot'y v 'coseand v -sine in the formof electrical quantities. The value h -cot'y from the transducer 53 isfirst multiplied in block 55 by dfir/ dt, from the tachometric dynamo51, thus obtaining the value p, in accordance with equation (Ila).Secondly, in block 56 in accordance with equation (Ilb) the value q isformed as the time derivative ofsaid value of h 'cot y and fed via astabilizing circuit 57, from which the stabilized value fiis obtained,to the block 58 which forms the quotient ti/ 7 the value p from block 55being stabilized in a stabilizing circuit 59 and fed as the value 5 intothe block 58.

By means of a computing unit including two control circuits consistingof the elements 60 to 68 and with the aid of the value fi/fi from block58 and the value tane-coty from the electromechanical transducer 54 thevalues B and cot(B +tll) are determined. The computer unit includes aresolver 60 which supplies at its outputs the values sin(B ill) andcos(,8 ill) as electrical quantities, the angle of rotation of the shaftof said resolver 60 corresponding to the value [3 +ill. In the block 61the value cot(B ill) is formed as a quotient of the two output values ofthe resolver 60. The computer circuit also includes a second resolver 62the angle of rotation of which corresponds to the value I! and whichsupplies the value sintll as an electrical output quantity, said valuebeing devided in the block 63 by the value sin (B ill) from the firstresolver. The output value cot(B Ill) from block 61, which representsthe right-hand side of equation (III), is compared in block 64, which isconstructed as an amplifier, with the value fi/P from block 58, whichrepresents the lefthand side of equation (Ill). The value sin \ll/sin(Bill) from block 63, corresponding to the left-hand side of equation (I),is compared in block 66 with the value tane-cot'y from theelectromechanical transducer 54 corresponding to the right-hand side ofequation (I). The result of the comparison in the blocks 64 and 66,constructed as amplifiers, is used to control the servomotors 65 and 67respectively by means of which the shafts of the resolvers 60 and 62respectively are rotated until the blocks 64 and 66 are balanced, i.e.,measure identity. At balance the conditions of equations (I) and (III)are fulfilled and the correct values of (B, 111) and ill correspondingto the angle of rotation of the shafts of the resolvers and of cot(B+tll) as electrical output quantity from block 61 are established. In amechanical subtracting device 68, for example a differential gear, thedifference between the angles of rotation of the two resolver shafts isformed, thus obtaining the value [3 which is an output quantity of thecomputer, as the angle of rotation of a shaft. Said shaft drives interalia a tachometric dynamo 69 which via a stabilizing circuit 70generates the value y T as an electrical quantity. The arrangement ofthe stabilizing circuits 58, 59 and 70 is shown at 150.

The value cot (8 ill) from block 61 is multiplied in block 71 by thevalue 0.5 sinZ'y from the electromechanical transducer 53 and theproduct obtained from said block 71 is multiplied in block 72 by thevalue a: 'y r from block 70, thus obtaining the value w y T inaccordance with equation (IV).

The part of the computer which with the aid of a ballistic computer Bcalculates the functions tank and tanp. of the lead angle increments kand u and the gravity compensation angle a will be describedhereinafter. As before, the calculation of the distance between gun andthe target will first be described, forming the basis of equations (VII)and (IX). The output shaft of the subtraction device 68, whose angle ofrotation corresponds to the value 3,, drives a resolver 73 whichsupplies the value sinB in the form of an electrical quantity. In block74 the value F from block 59 is divided by said value sinB In block 75the value v,,-cose from the electromechanical transducer 54 is dividedby the quotient thus obtained in block 74, thus giving the value maccording to equation (VIII), which is multiplied in block 76 by theconstant factor h to obtain the value mh The value v -sine from theelectromechanical transducer 54 is integrated in the block 77 withrespect to time, [=0 being the instant at which the target is picked upat the point P An the other hand, the value v -sins is multiplied inblock 78 by the value t of the projectile flight time calculated in theballistic computer B. The two products v,,-siner from block 77 andv,,'sine't from block 78 are added in block 79, which contains asummation circuit, thus obtaining the value v,,'sine'(t+r which is fedwith a negative sign into a block 80 including a summation circuit,where it is deducted from the value mh, from block 76. The output valueof block 80 corresponding to the difference between the two input valuesis further divided in block ill in accordance with equation Vll by thevalue sin-y from the electromechanical transducer 53 to obtain the valuew ofthe target range, which is fed into the ballistic computer B.

In addition to the calculated value of the target range w, the valuescos y and W from the electromechanical transducer 53 are fed lit i0 theballistic computer B, which then calculates the projectile flight time tand the gravity compensation anglea, which is an output quantity of thecomputer.

In accordance with equation (V) in block 82 the output value tank of thecomputer is calculated as a product of the value t from the ballisticcomputer B and he al a ut esasa ss mait block The output value tanp. ofthe computer is formed in ac-' cordance with equation (VI) bymultiplying in block 83 the value t from the ballistic computer B by thevalue anr from block 72.

In block 84 the derivative 0) with respect to time ,of the value 11obtained as an electrical quantity at the output ofthe ballisticcomputer B is formed. The value o thus obtained is added in block 85,which contains a summation circuit, to the value an 7 1 from block 72,

thus obtaining the output value to y of the computer. The value of theoutput of the ballistic computer B is also converted in a unit which isnot illustrated in the drawings by means of an amplifier and aservomotor into the rotation of a shaft and fed in this form into thesubstraction unit 52 at the input of the analog computer.

Instead of the resolvers 60, 62 and 73 other suitable functiongenerators, for example, sine-cosine potentiometers or computingcapacitors may be used.

It may be convenient to construct the computer as a hybrid computer inwhich elements of the digital computer type and of the analog computertype are combined, in particular to obtain a rapid and accuratecomputer.

In the examples of embodiment described above the gun and the targetacquisition device have the same location, denoted in FIGS. 1 to 3 by 0.However, if the locations are different the ballistic computer may be sodesigned that in addition to the gravity compensation angle a and thelead angle components k and y. it calculates two further correctionvalues k,, and #K for the elevation angle and the lateral angle of thetarget acquisition device, which cancel out the difference in location.

FIG. 6 shows an adapter device which converts the output quantities ofthe computer into the form necessary for controlling the drives of thegun and of the sighting device. The blocks 88 to 92 containdigitalanalog converters and convert the digital output quantities ofthe digital computer into analog form. The analog value of B formed inblock 88 is one of the output quantities of the adapter. In block 93,which contains a function converter, the value p, is obtained from theanalog value of tanu formed in block 90. The value a thus obtained isadded in block 94, which contains a summation circuit, to the value fromblock 89 and the value a p. forms an output quantity of the adapter. Thevalue tank is used to form the valuek in a block 95 containing afunction converter, The value of w y T calculated by the computer is fedafter conversion to analog form in block 92 to a potentiometer 98. Atthe potentio-meter 98 a fraction or y of the calculated value ofw y T istapped off. In the case of manual control the value in 7 1 set by thegun operator at the control lever K is fed into the input :1 of theadapter and supplied as reference value to an amplifier 96, to which iny T is also supplied and which compares to y with the reference value toy During this normalizing procedure of a) 7 the amplifier 96 controls aservometer 97 actuating the potentiometer 98 in such a manner that theoutput value to y of the adapter tapped from the potentiometer is equalto the value at y 1 supplied during the manual control to the gundrives. This ensures a smooth passage from the manual control to theautomatic tracking. During the automatic tracking the two inputs ofblock 96, as can be seen from FIG. 7, are short circuited and theposition of the potentiometer 98 thereafter remains unchanged.

When using an analog computer as shown for example in FIG. 5, the blocks88 to 92 of the adapter which contain the digital-analog converter maybe dispensed with.

In the block diagram illustrated in FIG. 7 a gun W is laterally andvertically pivotal and movable in these directions by means of avertical and lateral drive G. In the initial phase of a trackingoperation, in which the gunner brings the sighting device V onto thetarget by means of a lever control K, the switches 102 and 104 are intheir positions shown in dashed line and are controlled by the switch S.In this initial phase the values to y T and w a T are fed to the gundrives G from the lever control K. A computer R, which may be a digitalcomputer in accordance with FIG. 4 or an analog computer in accordancewith FIG. 5, is continuously supplied with the lateral and elevationalangular position d and U of the gun measured thereat, and the estimatedvalues of the flight path inclination i e and the flight velocity v, arefed manually into the computer R. If the computer is a digital computerthe values measured at the weapon of and T are fed to the computer incoded form as electrical signals. In the case of an analog computerthese values are fed to the latter in the form of angles of rotation ofthe shafts.

The output quantities of the computer R are fed to an adapter D which isillustrated in detail in FIG. 6 and has already been fully described.There is also shown in FIG. 7 an autocontrol device E which isillustrated in detail in FIG. 9, the operation of which will bedescribed with reference to FIGS. 7a and 9.

In FIG. 7a a modified embodiment is illustrated which is similar to thatof FIG. 7. In the embodiment of FIG. 7a a lever control K is providedtoo, which is operated by a control lever which influences bothdirectional movements, i.e., the lateral velocity to U T and theelevational, velocity 0) y T of the gun. The gun W is driven by the gundrives G. The lateral angle U and the elevational angle qS are taken viasuitable coding means continuously from the gun and fed to a computer R.In addition to these values, the target velocity, which is generally fedin as an estimated value v,,, and the inclination e of the target pathto the horizontal are fed to the computer R. The angle of inclination eof the target path to the horizontal is also generally fed in as anestimated value. The computer R provides from the input values a' v, ande supplied thereto the output values 8 a, tan .1.. tan A and ar flom t he val u the values for flie lateral lead); and the elevational lead uaswell as the gravity compensation angle a are determined in an adapterdevice D. It is assumed here that the sight is mounted on the gun andparticipates in the movements thereof so that the axis of the sight mustbe pivoted with respect to the barrel axis of the gun by the lead anglesand the gravity compensation angle.

In addition, the adapter device D carries out an adjustment orstandardization of the value of w y T calculated by the computer. Theadjusted value of w 7 supplied by the adapter device D is denoted inFIG. 7a by w y The adjustment is made by feeding the values to y Tsupplied during manual control by means of the control lever K in theinitial phase of the target tracking, i.e., the period in which thetarget is followed manually a's comparison values via the switch closedduring this phase and the connection d to the adapter device D andadjusting these values to the calculated values to y T from the computerR, as will be described in detail hereinafter. An autocontrol device E,which will also be described in detail hereinafter, supplies a lateralangular velocity w (r which is analogously adjusted to the values 0: 0'T supplied by the control lever K during manual control, these lattervalues being fed during the manual control via the switch S 4 to the gundrives G and simultaneously to the connection a of the autocontroldevice E. The adjusted values w y and w are not used during the initialphase of the target tracking, in which the switches S and S, assume theposition shown in dashed line in FIG. 7a. However, the adjustment ofthese values is essential in order to ensure a smooth continuoustransition of the lateral and elevational angular velocities supplied tothe gun drives G when switching from manual to automatic control, whenthe switches S and S, are moved from the positions shown in dashed lineto the full-line positions.

In the example of embodiment according to FIG. 7a two summation devicesA and A are provided which each add a fraction of the values of w y Tand w 0' T supplied by the control lever additionally to the values to yand w a respectively. These fractions are tapped off at voltage dividersW W and W W, via switches S and S respectively. The ratio between theresistances W W and W W respectively, may be made for example 1:19 sothat in each case onetwentieth of the values of w y T and to (T Tsupplied by the control lever are additionally fed to the summationdevices A, and A When the operator has picked up the target and exactlyfollowed it manually for a brief moment in the initial phase of thetarget tracking, he operates by means of the switch S the switches S andS, in such a manner that the latter are moved into the full-lineposition shown in FIG.7a. The values a) y and w supplied by the computerR, i.e., the adapter device D and the autocontrol device E are thensupplied to the summation devices A and A Since the switch S is notactuated as this is done, the switches S and 5,, remain in the full-lineposition shown in FIG. 1, and consequently one-twentieth of the valuesofw y T and w a T supplied by the control lever continues to be fed tothe summation devices A and A The control lever can thus be used in theautomated control for correcting the angular velocities supplied by thecomputer means R, D and E and fed to the gun drives G. Consequently, inthe control system according to FIG. 7a the lever control is convertedto a precision control without the need of additional provisions.

Instead of the fixed voltage dividers W W and W W variablepotentiometers may be provided. The tapped-off fractions of the lateraland elevational angular velocities w a T and w y T may then be differentfrom each other and can also be varied. A change in the magnitude of thetapped-off fractions of w a T and w 7 T may be particularly advantageouswhen the apparatus is used for low-speed objects after having been usedto track high-speed objects, e.g. when going from highspeed fighterplane tracking to low-speed helicopter tracking.

The output value B of the adapter is fed to an autocontrol device E.Said autocontrol device E will be explained in detail hereinafter. Theequations on which the autocontrol is based may be derived from FIG. 8.In FIG. 8 the position of the gun is denoted by 0. Since it is assumedthat the sight is mounted on the gun, O is also the position of thesight. The dashed line Sp represents the trace of the flight path in thehorizontal plane and w the horizontal projection of the distance w atimpact w forming with the line Sp and also with the straight line Spparallel to said line the angle E The horizontal component of thedistance to the change-over-puint is denoted in F IG. 8 by w min, thedistance to the change-over-point being the shortest distance betweenthe position of the gun or the target acquisition device respectivelyand the target path.

According to FIG. 8 the equation is true, wherein v,,,,,, is constantfor a given tracking operation. Differentiation of the above equationwith respect to time yields v of the target or the velocity with whichthe point T' moves along the line Sp. With w =w ,,/sinB;

it is then possible to write wBr= BT/dr) /w min)' fl1' wherein the valuew/wmi,l is constant for a given tracking operation. Equation (X) mayalso be written in the form milb' the integration of which leads to witht= ist C -cot B To It is thus possible to write BTW arc smear a;(iv/TEJJ-il I m The autocontrol device illustrated in FIG. 9 includes aswitch 106 which during the initial phase ofthe target tracking, inwhich the operator brings the sight to bear on the target manually,takes up the position shown in dashed line. The value B calculated inthe computer R and fed via the adapter D (FIG. 7) as an electricalquantity is supplied in this case to a positioning device whichcomprises an amplifier 108, a servomotor 110 and a potentiometer 112 andin accordance with the value [3 turns the shaft shown in dotted lines ofthe servomotor 110, said shaft in turn pivoting the slider 116 of apotentiometer 114. The resistance of the potentiometer 114 isproportional to sin /3 The potentiometer 114 is connected in series witha resistance 118 which is variable for adjustment purposes and apotentiometer 120 to a voltage source which supplies a constant director alternating voltage. The voltage tapped by the slider 116 from thepotentiometer 114 is fed to the output b of the autocontrol device andto an ampliher 122. Also supplied to the amplifier 122 is the value 1 vT which is provided via the input a by the lever control K in theinitial phase of the tracking (FIG. 7). A servomotor 124 controlled bythe amplifier 122 actuates the potentiometer 120, which is thus adjustedso that the voltage tapped at the potentiometer 114 coincides with thevalue m QLSIJPPIIBCI by the lever control potentiometer 114, which isset by adjusting the potentiometer 120.

In accordance w i th equation (X) the product of (w/ W ml|i) IrI BT=war, i.e.. the voltag e tappedTrom the potentiometer 114, is equal to(051. Since the angles o and ,B differ only by a constant angle w, theirangular velocities are identical. The value of m B T adjusted by thevalue at supplied by the control lever K is denoted by m to indicatethat this is an adjusted value which when switching from manual controlto automatic tracking ensures a smooth transition.

If during the initial phase of the tracking the operator has followedthe target by means of the manual control accurately for a shortdistance, he can then switch to automatic tracking by actuating theswitch 5 (FIG. 7). Actuation of the switch S simultaneously results inswitching over of the switch 106 (FIG. 9) into the position shown infull line via the input c of the autocontrol device. The autocontroldevice then no longer obtains the value B from the computer but forms itin accordance with equation (XI) with the aid of the circuit includingthe blocks 126, 132, 134 and 136. During automatic tracking the twoinputs of the amplifier 122, as shown in FIG. 7 are short circuited sothat the position of the potentiometer and thus the current flowingthrough the resistances 114, 118 and 120 and the value of w/w,,.,-, thenremain constant.

On switching over to automatic tracking the switch 128 is also actuated,thus initiating irg. block l26 the g P integratimi overtime t of thevalue ITV/WI min taken off the resistance 118. Furthermore. on switchingover the switch 130 is closed for a brief instant in order to scan thevalue Br supplied at the instant of the switchingover operation by thecomputer via the adapter, said value representing the value B forcalculating [3 from equation (XI). The value B is converted in block132, which contains a function member, into the value cot ,8 and storedin this form, being fed during the automatic tracking constantly intothe block 134 containing a summation circuit, where it is added to thevalue supplied by the integrator, thus obtaining the value cot B whichis converted in the block 136 containing a function converter into thevalue B The block 136 may for example comprise a diode network forconverting cos B to B The value of [3 thus produced is supplied, as waspreviously the value ,8, calculated by the computer, to the positioningdevice including the elements 108, 110 and 112, said device actuatingthe slider 116 of the potentiometer 114.

The output value at a of the autocontrol is fed via the output b to thelateral drive of the gun.

By integration in block 126 a continuous variation of the position ofthe slider 116 on the potentiometer 114 is effected and corresponds tothe variation of B,-, which corresponds to a rectilinear continuedmotion of the target at constant velocity. After switching from manualcontrol to automatic target tracking the value w [3 T tapped from thepotentiometer 114 and leaving the autocontrol device E as m a is fed tothe gun drives G via the switch 104 in case of the control systemaccording to FIG. 7 and via the swtich S and the summation device A, incase of the control system acw min cording to FIG. 7a. Fruthermore, onswitching from manual control to auto m atic trackin g the value am* isfed to the gun drives via the svTitch 165555? the control systemaccording to FIG. 7 and via the switch S and the summation device A, incase of the control system according to FIG. 7a. As described inconnection with the adapter according to FIG. 6, the value w is adjustedin the initial phase, in which the tracking is done manually, to thevalue am supplied by the control lever K VB ui'' connection? and consequerfil'y on switching from manual control to automatic control thevalue of the angular velocity of (i1;- fed to the gun drives G does notexhibit a jump.

In the examples of embodiment described herein it is assumed that thesighting device is mounted on the gun W and participates in the pivotmovements of the latter.

To take account of the lead and of the gravity compensation angle thevalues A and a p. from the adapter device D are fed to the sightingdevice V and control the position of the sighting device and gun withrespect to each other. During the initial phase of the tracking, inwhich the operator brings the sight and the gun to bear on the targetmanually, the computer R supports this manual control by calculating thelead angle and the comepnsation angle.

The autocontrol device E, which after switching from manual control toautomatic control automatically produces the lateral angle velocity w,on the basis of equations (X) and (X1), is not absolutely essential toautomatic tracking. The lateral angle velocity may also be supplied tothe gun drives G from the outputs shown in dotted line in the computer.In this case, analogously to the calculated elevational angular velocitytow. the calculated lateral angular velocity mgr is also adjusted to thelateral angular velocity w, supplied by the manual control so that anormalized value of (1)51 is av aila b le 9g switching ov e fla smoothtransition is thus ensured. In such a control arrangement withoutautocontrol E a continuous tracking is ensured, enhanced due to theinertia of the gun drives.

Particularly in the last-described control system without autocontroldevice the possibility according to this invention of correcting thecalculated values of the angular veocties after switching from manual toautomatic control is very advantageous. It may be convenient to correctonly the lateral angular velocity and to dispense with a correction ofthe elevational angular velocity which is calculated in the computer inaccordance with equation (IV). This may be done in the con trol systemaccording to FIG. 7a by opening the switch 8, before commencement of atarget tracking. It may also be expedient for certain high speed aerialtargets to dispense with the possibility of making a correction from thestart. In this case, the switches S and S, are opened beforecommencement of the target tracking by actuating the so-calledautoswitch S In the drawings and specification, there have been setforth preferred embodiments of the invention and although specific termsare employed, they are used in a generic and descriptive sense only andnot for purposes of limitation. It will be apparent to those skilled inthe art, to whom the disclosure is directed, that variations andmodifications may be made without departing from the essence of theinvention which should be broadly construed in view of the valuabletechnological development disclosed.

What is claimed is:

l. A method of controlling motor-driven devices mounted on two axes andadapted to be directed onto a moving target, the motion of which isassumed to be rectilinear uniform, and wherein the target is manuallytracked at least during initial tracking of the target by controlling atleast one of the devices to follow the target, comprising the steps ofcontinuously deriving signals of the lateral angle aand of the elevationangle 4) from the device to the target in accordance with the manualtracking, supplying the derived signals to computer means, supplying thecomputer means with sig nals corresponding to the target velocity v andthe angle of inclination e of the target path with respect to thehorizontal plane, and processing by the computer means of the suppliedsignals to calculate control quantities for each axis which quantitiesare to be supplied to the motor-driven devices for substantiallyautomatically controlling the drive thereof.

2. A method according to claim 1, wherein the step of processingincludes representing the target motion in polar coordinate form in acotangent plane, and representing the angle ofinclination e by an angleill arranged in the cotangent plane and lying between the projection ofthe target path on the cotangent plane and the projection on thecotangent plane of the projection of the target path in the horizontalplane.

3. A method according to claim 2, including the step of estimating thetarget velocity v.

4. A method according to claim 2, including the step of estimating theangle of inclination e of the target path.

5. A method for changing from manual to automatic control ofmotor-driven devices adapted to be directed onto moving targets,comprising the steps of manually tracking the target and manuallycontrolling the generation of signal values in the form of controlquantities of the lateral angular velocity (0 and the elevationalangular velocity my, supplying the control quantities to the drive ofthe device adapted to be directed onto the target, generating signals ina computer means on the basis of the manually generated signal values ofthe angular velocities of control quantities of the lateral angularvelocity w,* and of the elevational angular velocity an to obtain ananticipatory control function for at least one of facilitating andautomating the target tracking, and after accurately manually directingthe motor-driven device onto the target changing from manual toautomatic control by at least partially replacing the manually generatedcontrol quantity signal values supplied to the device by the computergenerated control quantity signal values.

6. A method according to claim 5, including the step of adjusting thecomputer generated signal values w,,* and an of the lateral andelevational angular ve locities to manually generaTd signal values ofsuch angular velocities prior to changing from manual to automaticcontrol.

7. A method according to claim 5, wherein the step of replacing themanually generated control quantities by the computer generated controlquantities includes only partially replacing the manually generatedcontrol quantities such that a fraction of about 3-20 percent of themanually generated control quantities are supplied to the drive of thedevice for manual correction of the tracking.

8. A method according to claim 7, including the step of continuouslyadjusting the fraction of the lateral and elevational angular velocitieswhich are supplied to the drive of the device after changing toautomatic control.

9. A method according to claim 5, wherein the motor-driven device is agun having a target acquisition device mounted thereon and participatingin the movements thereof, durther including the steps of generatingsignals in the computer means of lead angles A and p. and gravitycompensation angle a for the gun, moving the target acquisition devicewith respect to the barrel axis of the gun by the lead angles A and p.and the gravity compensation angle a, and accounting for the variationwith time on of the gravity compensation angle a in generating thecomputer signal valu es of the lateral and elevational angularvelocities for the gun.

10. An apparatus for controlling motor-driven devices mounted on twoaxes and adapted to be directed onto a moving target, the target beingfollowed by at least one of the devices, comprising means for derivingsignal values of the lateral angle and the elevation angle d) from thedevice to the target, first means for supplying the derived signalvalues to computer means, second means for supplying the computer meanswith signals corresponding to the target velocity v and the angle ofinclination e of the target path with respect to the horizontal plane.said computer means including a first computer unit for processing thesupplied signal values in accordance with the equations sin llI/Sll'l(13+ #1) tan e-cot y;

h cot y A B/A(h cot 'y) cot (B+tl1) to provide signal values of at leastone of the angles :1; and B and trigonometrical functions thereof, and asecond computer unit means responsive to the output signal values of thefirst computing unit for generating signal values in accordance with theequation wy= 0.5 sin 2v, cot (13+ kl'QB to provide a signal value of theelevational angular velocity my, said second computer unit furtherincluding means for at least one of differentiating the output signalvalue B of the lateral angle and forming differences between the outputsignal values of B to provide a signal value of the lateral angularvelocity (u 11. An apparatus according to claim 10, wherein saidcomputer means generates a signal of the distance to the target inaccordance with the equation and ballistic computer means responsive tothe output signal of the range for generating signal values of thegravity compensation angle a and the projectile flight time l 12. Anapparatus according to claim 11, wherein said computer means furtherincludes multiplying computer unit means responsive to the output ofsaid second computer unit means and said ballistic computer means forgenerating signal values of the tangent of the elevational lead angle p.and of the lateral lead angle A in accordance with the equations tan A:(UBfn, and; and function converter means responsive to the output signalvalues of said multiplying computer unit means for obtaining the inversefunction of the output signal values to provide signal values of p. andA.

13. An apparatus according to claim 12, further comprising autocontrolmeans including a sine squared potentiometer whose resistance varieswith the rotation of a slider in accordance with the square of the sineof the angle of rotation and a first self-balancing control circuitresponsive to the output of the computer means for swinging the sliderof the sine squared potentiometer in accordance with the signal valuegenerated by the computer means of the lateral angle B to provide aresistance value of sin B, a second control circuit for adjusting theslider of a current regulating potentiometer for setting the currentflowing through the sine squared potentiometer to a value, constant fora given tracking operation, of the quotient w/w' forrngdfrom thehorizontal component w of the target velocity v and the minimum valuew'min of the horizontal component of the target range, the setting beingeffected by adjusting the voltage tapped from the sine squaredpotentiometer in accordance with the equation w w/w',,.,-,.'Sin B andcorresponding to the lateral angular velocity (05 by the voltage signalvalue 0),, of the lateral angular velocity supplied by a control leverfor effecting manual tracking, an integrator for generating a signal ofcot B in accordance with the equation a function converter forconverting the signal cot B to the signal value B, and a switch meansbeing operated to change from manual control to automatic control toreplace the signal value ofB generated by the computer means by thesignal value B generated by said function converter.

14. A method of tracking a target by an operator directing amotor-driven device onto a moving target wherein the motor-driven deviceis a target acquisition device, comprising the steps of manuallytracking the target and manually generating signal values in accordancewith the manual tracking, supplying the manually generated values to thedrive for the device and to a computer m'eans, generating signal valuesin the computer means on the basis of the manually generated signalvalues, the computer generated signal values being adapted to besupplied to the drive of the device, and supplying the computergenerated signal values to the drive of the device in place of themanually generated signal values at a time selected by the operator whenthe manual tracking of the traget has been determined to be ofapproximately the greatest possible accuracy.

15. A method according to claim 14, wherein the step of manuallytracking the target and manually generating signal values forcontrolling the drive of the device includes tracking the target for aperiod of time sufficient to ensure that the motion of the targetacquisition device corresponds to the motion of the target.

16. A method according to claim 14, wherein the step of manuallytracking the target and manually generating signal values forcontrolling the drive of the device includes manually directing thetarget acquisition device along the path of the target such that themotion of the target acquisition device corresponds to the motion of thetarget.

17. An apparatus for changing from manual to automatic control ofmotor-driven devices adapted to be directed onto moving targets,comprising a manual control for supplying signal values of the lateralangular velocity and of the elevational angular velocity for controllingthe motor-driven devices, computer means responsive to the signal valuesof the lateral and elevational angles from the manual control forgenerating luya t st yi ans .,mi9. lateral i i ational angularvelocities for the drive of the devices, two summation devices, saidcomputer means including an anticipatory control means, the generatedsignals of control quantities being fed to the anticipatory controlmeans for at least one of the functions of facilitating and automatingthe target tracking, the signal values a) and a, of the lateral andelevational angular velocities from the manual control being fed directly to the first input of said two summation devices whose outputsignal values are fed to the drives of the devices, and a fraction ofabout 5 20 percent of the signal values w, a nd tgv of the lateral a n de levatml angular velocities sup p lie d by the Enual control being fedvia voltage divider means to a second input of said two summationdevices, and a change-over switch means being provided in the connectionbetween the manual control and the summation devices for supplying thesignal values w,,* and of the lateral and elevational angular velocitiesgenerated by the computer means to the first input of the summationdevices.

1. A method of controlling motor-driven devices mounted on two axes andadapted to be directed onto a moving target, the motion of which isassumed to be rectilinear uniform, and wherein the target is manuallytracked at least during initial tracking of the target by controlling atleast one of the devices to follow the target, comprising the steps ofcontinuously deriving signals of the lateral angle sigma and of theelevation angle phi from the device to the target in accordance with themanual tracking, supplying the derived signals to computer means,supplying the computer means with signals corresponding to the targetvelocity v and the angle of inclination Epsilon of the target path withrespect to the horizontal plane, and processing by the computer means ofthe supplied signals to calculate control quantities for each axis whichquantities are to be supplied to the motor-driven devices forsubstantially automatically controlling the drive thereof.
 2. A methodaccording to claim 1, wherein the step of processing includesrepresenting the target motion in polar coordinate form in a cotangentplane, and representing the angle of inclination epsilon by an angle psiarranged in the cotangent plane and lying between the projection of thetarget path on the cotangent plane and the projection on the cotangentplane of the projection of the target path in the horizontal plane.
 3. Amethod according to claim 2, including the step of estimating the targetvelocity v.
 4. A method according to claim 2, including the step ofestimating the angle of inclination epsilon of the target path.
 5. Amethod for changing from manual to automatic control of motor-drivendevices adapted to be directed onto moving targets, comprising the stepsof manually tracking the target and manually controlling the generationof signal values in the form of control quantities of the lateralangular velocity omega and the elevational angular velocity omega ,supplying the control quantities to the drive of the device adapted tobe directed onto the target, generating signals in a computer means onthe basis of the manually generated signal values of the angularvelocities of control quantities of the lateral angular velocity omega *and of the elevational angular velocity omega to obtain an anticipatorycontrol function for at least one of facilitating and automating thetarget tracking, and after accurately manually directing themotor-driven device onto the target changing from manual to automaticcontrol by at least partially replacing the manually generated controlquantity signal values supplied to the device by the computer generatedcontrol quantity signal values.
 6. A method according to claim 5,including the step of adjusting the computer generated signal valuesomega * and omega of the lateral and elevational angular velocities tothe maNually generatd signal values of such angular velocities prior tochanging from manual to automatic control.
 7. A method according toclaim 5, wherein the step of replacing the manually generated controlquantities by the computer generated control quantities includes onlypartially replacing the manually generated control quantities such thata fraction of about 3-20 percent of the manually generated controlquantities are supplied to the drive of the device for manual correctionof the tracking.
 8. A method according to claim 7, including the step ofcontinuously adjusting the fraction of the lateral and elevationalangular velocities which are supplied to the drive of the device afterchanging to automatic control.
 9. A method according to claim 5, whereinthe motor-driven device is a gun having a target acquisition devicemounted thereon and participating in the movements thereof, durtherincluding the steps of generating signals in the computer means of leadangles lambda and Mu and gravity compensation angle Alpha for the gun,moving the target acquisition device with respect to the barrel axis ofthe gun by the lead angles lambda and Mu and the gravity compensationangle Alpha , and accounting for the variation with time omega of thegravity compensation angle Alpha in generating the computer signalvalues of the lateral and elevational angular velocities for the gun.10. An apparatus for controlling motor-driven devices mounted on twoaxes and adapted to be directed onto a moving target, the target beingfollowed by at least one of the devices, comprising means for derivingsignal values of the lateral angle sigma and the elevation angle phifrom the device to the target, first means for supplying the derivedsignal values to computer means, second means for supplying the computermeans with signals corresponding to the target velocity v and the angleof inclination epsilon of the target path with respect to the horizontalplane, said computer means including a first computer unit forprocessing the supplied signal values in accordance with the equationssin psi /sin ( Beta + psi ) tan epsilon . cot gamma ; hc . cot gammaDelta Beta / Delta (hc . cot gamma ) cot ( Beta + psi ) to providesignal values of at least one of the angles psi and Beta andtrigonometrical functions thereof, and a second computer unit meansresponsive to the output signal values of the first computing unit forgenerating signal values in accordance with the equation omega 0.5 sin 2gamma , cot ( Beta + psi ) . omega to provide a signal value of theelevational angular velocity omega gamma , said second computer unitfurther including means for at least one of differentiating the outputsignal value Beta of the lateral angle and forming differences betweenthe output signal values of Beta to provide a signal value of thelateral angular velocity omega .
 11. An apparatus according to claim 10,wherein said computer means generates a signal of the distance to thetarget in accordance with the equation m hc - v . (t+tG) . sin epsilon/sin gamma , and ballistic computer means responsive to the outputsignal of the range for generating signal values of the gravitycompensation angle Alpha and the projectile flight time tG.
 12. Anapparatus according to claim 11, wherein said computer means furtherincludes multiplying computer unit means responsive to the output ofsaid second computer unit means and said ballistic computer means forgenerating signal values of the tangent of the elevational lead angle Muand of the lateral lead angle lambda in accordance with the equationstan Mu omega gamma . tG and tan lambda omega . tG, and and functionconverter means responsive to the outpuT signal values of saidmultiplying computer unit means for obtaining the inverse function ofthe output signal values to provide signal values of Mu and lambda . 13.An apparatus according to claim 12, further comprising autocontrol meansincluding a sine squared potentiometer whose resistance varies with therotation of a slider in accordance with the square of the sine of theangle of rotation and a first self-balancing control circuit responsiveto the output of the computer means for swinging the slider of the sinesquared potentiometer in accordance with the signal value generated bythe computer means of the lateral angle Beta to provide a resistancevalue of sin2 Beta , a second control circuit for adjusting the sliderof a current regulating potentiometer for setting the current flowingthrough the sine squared potentiometer to a value, constant for a giventracking operation, of the quotient w/ ''min formed from the horizontalcomponent w of the target velocity v and the minimum value ''min of thehorizontal component of the target range, the setting being effected byadjusting the voltage tapped from the sine squared potentiometer inaccordance with the equation omega - w/ ''min . sin2 Beta andcorresponding to the lateral angular velocity omega by the voltagesignal value omega of the lateral angular velocity supplied by a controllever for effecting manual tracking, an integrator for generating asignal of cot Beta in accordance with the equation
 14. A method oftracking a target by an operator directing a motor-driven device onto amoving target wherein the motor-driven device is a target acquisitiondevice, comprising the steps of manually tracking the target andmanually generating signal values in accordance with the manualtracking, supplying the manually generated values to the drive for thedevice and to a computer means, generating signal values in the computermeans on the basis of the manually generated signal values, the computergenerated signal values being adapted to be supplied to the drive of thedevice, and supplying the computer generated signal values to the driveof the device in place of the manually generated signal values at a timeselected by the operator when the manual tracking of the traget has beendetermined to be of approximately the greatest possible accuracy.
 15. Amethod according to claim 14, wherein the step of manually tracking thetarget and manually generating signal values for controlling the driveof the device includes tracking the target for a period of timesufficient to ensure that the motion of the target acquisition devicecorresponds to the motion of the target.
 16. A method according to claim14, wherein the step of manually tracking the target and manuallygenerating signal values for controlling the drive of the deviceincludes manually directing the target acquisition device along the pathof the target such that the motion of the target acquisition devicecorresponds to the motion of the target.
 17. An apparatus for changingfrom manual to automatic control of motor-driven devices adapted to bedirected onto moving targets, comprising a manual control for supplyingsignal values of the lateral angular velocity and of the elevationalangular velocity for controlling the motor-driven devices, computermeans responsive to the signal values of the lateral and elevationalangles from the manual control for generating signal values omega * andomega * of the lateral and elevational angular velocities for the driveof the devices, two summation devices, said computeR means including ananticipatory control means, the generated signals of control quantitiesbeing fed to the anticipatory control means for at least one of thefunctions of facilitating and automating the target tracking, the signalvalues omega and omega of the lateral and elevational angular velocitiesfrom the manual control being fed directly to the first input of saidtwo summation devices whose output signal values are fed to the drivesof the devices, and a fraction of about 5 - 20 percent of the signalvalues omega and omega of the lateral and elevational angular velocitiessupplied by the manual control being fed via voltage divider means to asecond input of said two summation devices, and a change-over switchmeans being provided in the connection between the manual control andthe summation devices for supplying the signal values omega * andomega * of the lateral and elevational angular velocities generated bythe computer means to the first input of the summation devices.